The card owned the bundle storage (key derivation, {key}.json,
{key}.png and {key}_ch{n}.png, the shared trim budget) as static
members, and the cache page spelled the audio_analysis_cache directory
literal twice more.
Move the storage verbatim into AudioAnalysisDiskCache next to the
existing lease/trim policy. AudioAnalysisDiskCache.directoryIn is now
the only place that names the directory; the card's cacheDir and both
cache page call sites use it, with the page keeping its non-creating
behavior and await order. loadFromCache takes the card's network input
as a parameter instead of reading the field.
The 63-bit FNV-1a cache key stays local: lib/utils/hash_utils.dart
fnv1a32 uses a different basis, prime and width, so reusing it would
rename every cached bundle on devices.
zarzet